Low
4.10 on Ideal Logic Max Combi

Your boiler has lost communication with the sensor that monitors the outdoor temperature, which means it cannot automatically adjust its settings based on the weather.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Outside Sensor Fault

From this model's manual
Verified against the Ideal Logic Max Combi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's main control board loses the electrical signal from the sensor located on the exterior of your home. The most common reasons are a breakdown in the sensor's internal circuitry due to moisture ingress or damage to the thin communication wires connecting the sensor to the boiler.

This fault is often more frequent during autumn and winter as extreme temperature shifts or high winds can expose pre-existing damage to external wiring or the sensor housing itself.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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